On Mon, Aug 26, 2013 at 10:15 PM, Pavel Stehule <pavel.steh...@gmail.com> wrote: > Hello > > very nice! I tested it and works very well. > > And I looking for implementation in core. > > Two notes: > > * should to support string_agg and array_agg > > Regards > > Pavel > > > > 2013/8/26 Vik Fearing <vik.fear...@dalibo.com> >> >> On 08/26/2013 02:39 PM, Pavel Stehule wrote: >> > Hello >> > >> > Three years ago we worked on implementation of median function. >> > >> > >> > http://www.postgresql.org/message-id/aanlktimrksuoggsk7-gtxnvjjgl-1qvuqxiduszqw...@mail.gmail.com >> > >> > >> > Can we implement this function now? >> > >> > There are a few opened questions: >> > >> > * immutable parameters of aggregate functions >> > >> > * effective implementation when data are in memory >> > >> > * effective implementation when data are out of memory >> > >> > * effective implementation for usage as window function - running >> > median. >> > >> > Better than before, we can choose between hashing and sorting based >> > aggregation. But tuplesort implementation is not right for using as >> > window function. Second issue can be a not possible reusing of >> > tuplesort for more final functions - median, percentile in one query. >> > >> > Ideas how to solve this task? Can we move forward in some points? >> >> Take a look at the standard-compliant WITHIN GROUP that is currently in >> development for 9.4. >> >> http://www.postgresql.org/message-id/2b8b55b8ba82f83ef4e6070b95fb0...@news-out.riddles.org.uk >> >> -- >> Vik >> >
Thanks a ton! We will definitely look at supporting at the two functions you mentioned. Regards, Atri -- Regards, Atri l'apprenant -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers